Design and implementation of a new magnetron

Magnetrons are cross-field microwave vacuum tubes with a wide range of applications, usually consisting of a cylindrical anode and cathode. The main areas of use are microwave ovens, medical devices, communication and observation satellites and radars. Another important application area is fusion plasmas. In this thesis, two magnetron designs have been presented. One of these designs has 8 cavities in both anode and cathode (D4), whereas other design does not have a cathode cavity (D3). Parameters such as operating frequencies, electric field values and electron trajectories of D3 and D4 magnetrons have been examined. First of all, mathematical modeling of the designed magnetron was made and then simulation studies were started. In the simulation studies, eigen-frequency, particle tracking and particle in cell (PIC) analyzes were performed, respectively. The production of the D4 magnetron, which was designed according to the results obtained from the simulations, was started, and experimental studies were carried out both in the atmosphere and the vacuum conditions. The electric field and power density parameters of the magnetron under atmospheric conditions were investigated. Then, a Langmuir probe was designed to examine the parameters of magnetic plasmas, which is one of the application areas of the magnetron, and under the vacuum conditions the electron temperature and density in the magnetic plasma were investigated. According to the eigen-frequency analysis, the π mode frequency of the D3 magnetron was found to be 9.115 GHz, and the π mode frequency of the D4 magnetron was 9.112 GHz. In addition, the maximum electric field values of the magnetrons at these frequencies were obtained as 4.883 x 10^8 V/m and 4.994 x 10^8 V/m, respectively. In the particle in cell (PIC) analyzes, the operating frequency of the D3 magnetron at 50 kV voltage and 0,075 T magnetic field value was found to be 10.264 GHz. The operating frequency of the D4 magnetron at 50 kV voltage and 0.074 T magnetic field value was found to be 9.1 GHz. In addition, it has been observed that the D4 magnetron at 60 kV voltage and 0.07 T magnetic field operates in dual band at frequencies of 9.108 GHz and 11.656 GHz. In the experimental studies under the atmospheric conditions, the maximum electric field value in the designed antenna was found as 129 V/m and the maximum power density value as 108.3 W/m^2 in the radial direction. The maximum electric field value was found to be 96.01 V/m at a distance of 10 cm from the antenna in the horizontal direction. In the studies carried out under vacuum conditions, the electron temperature in the magnetic plasma was found to be 307923 K (26.55 eV), while the electron density was found to be 7.6 x 10^10 m^-3.